<template>
  <div class="box" style="height:500px">
    <div class="xtx-slider">
      <ul class="slider-body" @mouseenter="clear" @mouseleave="star">
        <li
          class="slider-item"
          v-for="(item, i) in sliders"
          :key="i"
          :class="{ fade: curIndex === i }"

        >
        <!-- fade类名存在，当前图片就显示，不存在就不显示 -->
          <img :src="item.imgUrl" alt="" />
        </li>
      </ul>
      <!-- 圆圈切换按钮 -->
      <div class="slider-indicator">
        <span :class="{active:index===curIndex}" v-for="(item,index) in sliders" :key="index" @click="curIndex=index"></span>

      </div>
    </div>
  </div>
</template>
// 圆圈和图片的数量是一样的，下标值是对应的
// 记录一下当前点击的是哪一项
// // 需要根据记录下来的下标值，去配合：class,控制fade这个类名是否应该显示
<script>
import { ref } from 'vue'
export default {
  name: 'XtxSlider',
  props: {
    sliders: {
      type: Array,
      default () {
        return []
      }
    },
    // 是否自动轮播
    autoPlay: {
      type: Boolean,
      default: false
    }
  },
  setup () {
    const curIndex = ref(0)
    return {
      curIndex
    }
  },

  data () {
    return {
      index: 0,
      time: null
    }
  },
  created () {
    this.staloop()
  },
  methods: {
    staloop () {
      // 如果不开起自动轮播
      if (!this.autoPlay) {
        return false
      }
      this.time = window.setInterval(() => {
        this.curIndex++
        if (this.curIndex > this.sliders.length - 1) {
          this.curIndex = 0
        }
      }, 3000)
    },
    star () { // 鼠标移入事件
      this.staloop()// 让他再次执行
    },
    clear () { // 鼠标移除事件
      window.clearInterval(this.time)// 清楚定时器
    }
  }

}
</script>

<style scoped lang='less'>
.xtx-slider {
  width: 100%;
  height: 100%;
  min-width: 300px;
  min-height: 150px;
  position: relative;
  .slider {
    &-body {
      width: 100%;
      height: 100%;
    }
    &-item {
      width: 100%;
      height: 100%;
      position: absolute;
      left: 0;
      top: 0;
      opacity: 0;
      transition: opacity 0.5s linear;
      &.fade {
        opacity: 1;
        z-index: 1;
      }
      img {
        width: 100%;
        height: 100%;
      }
    }
    &-indicator {
      position: absolute;
      left: 0;
      bottom: 20px;
      z-index: 2;
      width: 100%;
      text-align: center;
      span {
        display: inline-block;
        width: 12px;
        height: 12px;
        background: rgba(0, 0, 0, 0.2);
        border-radius: 50%;
        cursor: pointer;
        ~ span {
          margin-left: 12px;
        }
        &.active {
          background: #fff;
        }
      }
    }
    &-btn {
      width: 44px;
      height: 44px;
      background: rgba(0, 0, 0, 0.2);
      color: #fff;
      border-radius: 50%;
      position: absolute;
      top: 228px;
      z-index: 2;
      text-align: center;
      line-height: 44px;
      opacity: 0;
      transition: all 0.5s;
      &.prev {
        left: 20px;
      }
      &.next {
        right: 20px;
      }
    }
  }
  &:hover {
    .slider-btn {
      opacity: 1;
    }
  }
}
</style>
